This application claims the priority of German application 198 43 024.8, filed in Germany on Sep. 19, 1998, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a reinforcement for a unitized body of a motor vehicle, which is located in a transverse plane between the wheel housings.
A reinforcement of this kind is known from German Patent 14 55 679, and relates to an end unit as an assembly for unitized bodies of motor vehicles. The end unit is designed as the front area of a motor vehicle with vertical side walls, each of said walls being provided with an indentation for wheels. In the vicinity of these indentations, a hat-shaped tower is provided in each side wall, said tower being connected with the respective side wall in the vicinity of the wheel housings with the aid of flanges. The hat-shaped tower serves to attach a shock absorber for example.
A transverse beam is located approximately at the level of the lower end of the windshield, said member being located in a transverse plane of the vehicle located between the wheel housings, and the two front chassis towers are connected permanently with one another in its upper area. In addition, the transverse beam is connected at each of its ends by a pressed panel with the side walls. The transverse beam is fastened to the pressed panels with the aid of a gusset that extends outward in the direction of the side walls, said gusset providing a three-dimensional support for the vehicle towers.
Since only the transverse beam is provided in the vicinity at the level of the side wall of the vehicle to stiffen the structure of the body-in-white, only a limited rigidity, especially torsional stiffness, is provided for the body-in-white.
A goal of the invention is to provide a reinforcement for a unitized body of a motor vehicle of the type described, which improves the stiffness of the body-in-white.
This goal is achieved according to the invention by a reinforcement of a unitized body of a motor vehicle, which is located in a transverse plane of the vehicle between lateral wheel housings, and which comprises a transverse beam that connects the wheel housings with one another in an upper area, wherein the transverse beam is located on the rear wheel housings and connected in an overlapping area in a reinforcing manner with a supporting plate of a parcel shelf.
In the reinforcement according to the invention, the transverse beam is located in the overlapping area together with a supporting plate of a parcel shelf at the rear wheel housings and is connected in a reinforcing manner with the supporting plate. By locating both the supporting plate and the transverse beam at the wheel arches, an especially stable reinforcement is produced that is very suitable for receiving torsional forces and especially clearly improves the torsional stiffness of the unitized body. In an advantageous manner, the transverse beam also improves the denting resistance of the supporting plate and prevents oscillation and flexing, especially in the vertical direction of the vehicle. The supporting plate is especially suited for accepting forces in the lengthwise direction of the vehicle, so that a reinforcement is produced overall that opposes the torsional forces.
Advantageous features of preferred embodiments of the reinforcement according to the invention are described herein and in the claims.
Thus, it has been found to be especially advantageous to make the transverse beam with a profile that is open on one side, said profile being able to be connected with the supporting plate to form a profile that is closed at least in certain areas. Thus, the tension strut for example can be shaped in simple fashion from sheet steel and then connected at least partially with the supporting plate. If the transverse beam is connected with the supporting plate over larger areas or over its entire length, the flexing of the supporting plate in the vertical direction of the vehicle can be significantly reduced.
If a damper tower is associated with the upper areas of each of the wheel housings, the transverse beam can be secured to the damper towers. The forces transmitted by the chassis to the damper towers can be accepted especially well by the transverse beam and the supporting plate. As a result, especially favorable torsional stiffness properties of the entire body-in-white can be achieved.
If the damper towers penetrate the supporting plate, an especially stable connection can be formed between the damper towers and the supporting plate, with the transverse beam located on the top of the supporting plate additionally allowing an extensive introduction of force from the damper towers into the transverse beam.
The supporting shoes at the ends of the transverse beam result in a large force-introduction-node between the damper towers and the transverse beam. These nodes can be enlarged even further by angle reinforcements located on the underside of the supporting plate which likewise are connected with the damper towers.
If recesses extending laterally outward from the tower openings are provided in the supporting plate, when assembly takes place, the supporting plate can be installed after the damper towers and side braces have already been installed, before the transverse beam and the angle reinforcements are attached.
Finally, it has been found to be especially advantageous to limit the supporting plate with front and rear supporting profiles that also provide support in order to make the supporting plate stiffer and especially to counteract the vertical flexing and oscillation in the vertical direction of the vehicle.